Improvement in scroll-sawing machines



n. ,MCCHESNM scRoLL-sAWING MACHINE.

No.173,319. A Patented Feb.a,1a7e..

`if,anysals. I Y I larm supports the upper saw-gate.

UNITED STATES PATENT Genion.

REUBEN MOOHESNEY, OIF. NEWARK, NEW JERSEY, A SSIGNOR OF ONE-THIRDHIS'RIGHT TO THOMAS B.,DAVIS, OF NEW YORK, N. Y.

IMPROVEM'ENT'IN SCROLL-SAWING MACHINES.

.Specification forming part of Letters Patent N0. 173,319, datedFebruary8, 1.876 ;v application filed August 30, 1875.

T o all whom 'it may concern Be it known that I, REUBEN McGHEsNEY, ofNewark, in the county of Essex and State of New Jersey, have inventedcertain Improvements in Scroll-Sawing Machines; Land I do hereby declarethat the following is a full, clear, and exact description of the same,reference bein ghad to the accompanying draw A ing, in which- Figure Iis a side view of a machine embodying my improvements. Figs. 2, 3, 4,and 5 are detail views, hereinafter referred to.

My invention relates to improvements in scrollsawing machines 5 and itconsists in certain details of construction, arrangement, andcombination of the various parts, for strengthening and preventingvibration of the trussed arm; for clamping the saw for raising andlowering the saw-gate frame; for guiding or supporting saws of differentthicknesses; and for accurately Vadjusting the table-all as hereinafterparticularly described.

' The pedestal A and trussed arm B are made in one piece of metal, thearm being of nearly elliptical'i'orm and the upper end of the pedestalterminating near the minor axis of the ellipse. The'ends 'of the arm area sufficient dista-nce apart to allow for the supporting of the tableand the admission of the work between it and the Vupper end of the arm.The lower end ofthe arm B supports the table and the lower saw-gate, andthe upper end of the On the outer periphery of the arm B, from thepedestal around to the upper end o t' the arm, at regula-r distancesapart, are studs a, having their outer ends provided with notches ordepressions, running longitudinally ofthe arm. A tension-brace, C',consisting of a wire cable or iron rod, passes over-the studs a, lyingin the notches or recesses, and has one end attached to the pedestal A,and the other end connected with the upper end of. the arm B vby meansof a screw turn-buckle, c, attached to the end of the cable, andengaging with -a screw-threaded stud or projection, 11,011 the arm B. Byturning this tightening device the brace 'C is strained to the properdegree of tension to strengthen the trussed arm and prevent vibrationthereofl when the machine isatwork. Instead of the turn-buckle, a rightand left hand nut may be used, and a thread may be formed on the end oft-he brace G i'or engagement with the lefthand nut. The

tightening devices may be applied to both ends ofthe brace, it desired,so as to strain. it in both directions.

Each ot' the sawgates is provided witha saw-clamping device, consistingof two pivoted bent levers or clamping-jaws and a slide for tighteningor loosening the saine, Figs. 1, 2,y and 3. Each lever R is bent in aform .resembling two sides ot' a square, and has at one end a hook, r.rIhe two levers-B R are pivoted to the saw-gate I), near the ends onwhich the hooks r are formed, with said hooks projecting inward towardeach other and with the opposite ends of the levers inclined outward andforming two sides o't' a triangle.

In the saw-gate P is a groove for guiding the slide or cross-bar S,which operates the jaws. This slide is formed with a tapering orwedge-shaped projection, s1, which works between the inner edges of thelong arms ot' the levers or jaws R, and with` two lugs orl lips, s2,which engage with the outer edges thereof,

so that when the slide S is moved toward the K saw the jaws are wedgedopen, and when the slideis moved in the opposite direction the jaws areclosed by the action of lthe lugs or lips s2 pressing inward aga-instthe outer edges of the jaws. Oneof these clamping devices is attached tothe upper gate and another to the lower gate, so that the motion of theupper slide in opening or closing thejaws is the reverse of thatY of thelower slide. The end of the saw is inserted between the hooks r r, sothat when the jaws are closed the saw is rmly clamped between the pointsof the hooks. The slide S is provided with a vertical elongation, hav'-ing a hook, t, at the end, for attaching the cord or band Iby which thesaw is driven, and when this cord or band is strained to the propertension it pulls on the slide S and Vinsures the proper clamping ofthesaw. In order to keep the jaws closed and hold the saw in place when thecord or band is disengaged or not strained taut, I employ a spring, Q,one end of which engages with a fixed point on the saw-gate and theother end engages with the slide S, with a tendency to force it in theproper direction to close the jaws. For im parting motion to the saw Iemploy two cords or bands, I J. One end of the band l is attached to awheel, H3, which oscillates on a stud attached to the arm B, and theother end connects with the upper saw-gate by means of the hook t, andthe band J is attached to the wheel and connects with the lower saw-gatein the same manner. rI he bands l J pass over-and under two oscillatinggrooved wheels or pulleys, I J", before reaching the vsaw-gates. Iprefer to make each of these wheels of four pieces of wood of qnadrantalform,joined together with the grain of the wood of the different piecesruning in ditferent directions; and in order to prevent splitting' orwarping of the wheel thus formed, l cut a supplemental groove at thebottom of the groove proper, and ll it with thread or yarn saturatedwith glue. The wheel H3 receives motion from a crankwheel, H2, by meansof a pitman, h, which I prefer to make of wood, split longitudinally forthe greater portion of its length, and having posts or braces insertedin the split portion, by which means I combine strength and lightness.The crank-wheel H2 is carried by the shaft of the main driving-pulley,which shaft has its bearings in an arm, H, extending outward from thepedestal A, by which means a degree of elasticity is imparted to themachine when in motion. The lower wheel or pulley Jx has a xed'bearing.The upper one lx has its bearing in the upper end of a lever, K, pivotedto 'a sliding frame, M, which carries the upper saw-gate, and works inways in thc upper end of the arm B. The lever K is provided with aspring-catch, l, for holding it in place in a vertical position, andallowing it to be inclined from such position when neces sary. Thesliding frame M is provided with a screw, m, the point of which bears ona projecting portion of the trussed arm.

By tightening or loosening the screw, the frame is raised or lowered,and the tension of the bands I and J and of the saw may be regulated tothe exact degree required without stopping the machine. j

The sliding saw-gate frame M is provided with a device (see Fig. 4) forholding it up, when desired, consisting of a pin or plunger, Ll, slidingin the frame M, and a spring bolt or catch, L2, working in a seat in thearm B, with the end of the bolt projecting outward from its seat, androunded so as to allow the pin Ll to readily slip over it.

When it is desired to remove the upper end of the saw from the clamp, inorder to insert it through a hole in the work, it is also desirable tohave the frame M out of the way while the work is being adjusted. Thisis readily accomplished by simply raising the frame until the pin L1 hasreached the level of the bolt L2, when the end of the bolt willimmediately spring out and project beyond its seat, and enter the socketin which the pin L1 works, and thus hold the frame in its raisedposition. By pushing the pin inward the bolt is forced back, and theframe allowed to descend.

Heretofore, in some machines of a similar character to this, the saw hasbeen provided with a device for guiding and supporting it between thegates, in which the saw worked in a slot or notch nearly correspondingwith the thickness of the blade, in consequence of which there wasconsiderable friction of the sides of the blade and of the teeth, and itwas necessary to change the guide when a saw of dif ferent thickness wasused. To remedy these defects, I employ a guiding and supporting device,(see Fig. 5,) consisting of a pin or bar, V, attached to the lowerportion of the frame M, and capable of adjustment therein, toaccommodate blades of ditferent widths. In the front or outer end of thepin is a Vshaped notch or recess, o, against which the back of the bladerests, and is thus guided and supported when in motion, and at the sametime friction of its sides or teeth is prevented. y Y

In consequence of the shape of the notch it will accommodate saws ofdifferent thicknesses, and therefore obviate the necessity for removingi't when the saw is changed.

The table D is attached to the lower end of the arm B by means ofa'semicircular plate E, the straight edge ofv whichis provided with lugse, through which bolts or screws pass into the under side of the table.Between the lugs e and the table are cushions or pads f, of rubber orother elastic substance. The vertical portion of the plate E isconnected with another plate by means of a pivot, a slot, and set-screw,and a pin and holes, by which means the table may be oscillated andinclined from a horizontal position.

When `the table is as near a level position as it is possible to attainby the adjustment of the pin gx in one of the holes e", and a stillnicer adjustment is desired, the screws or bolts are tightened orloosened, so as to clam p the pads f more or less tightly between thelugs and the table, by which means a perfectly level position may beobtained.

What I claim as new, and desire to secure by Letters Patent, is-

l. The saw-clamp, consisting of the pivoted levers or jaws R It, havingthe hooks 1' 1', and

the sliding cross-bar S, provided with the proi jection s1 and lugs orlips s2 s2, in combination with the saw-slide, and the cord or band I'orJ, substantially as herein described.

2. The sliding pill L1 and spring bolt or catch L2, in combination withthe arm B and sliding frame M, substantially as and for the purposeherein described.

3. The elastic pads or cushions j', in combination with the lugs e andtable D, substantially as and for the purpose shown and described.

R. MOOHESNEY. Witnesses:

BENJAMiN W. HOFFMAN, FRED HAYNEs.

